1 04 HISTORY OF GEOLOGY AND PALEONTOLOGY. 



species. The great chemist Lavoisier made several geological 

 sections through the Paris basin, and pointed out the alterna- 

 tion of littoral and pelagic deposits. The stratigraphical 

 succession established by Lavoisier was added to by Coupe's 

 detailed examination of exposures in the vicinity of Paris. 



The greatest work on the " Paris Basin" appeared in 1808, 

 in the Journal des Mines and Annales du Museum. The authors 

 were Brongniart, Professor of Mineralogy in the Natural 

 History Museum in Pans, and Cuvier, the famous zoo- 

 logist and palaeontologist. They drew up a systematic table 

 of the succession of stratigraphical horizons in accordance 

 primarily with the sequence of the deposits in the ground, 

 and with the particular fossils characterising each group of 

 deposits ; the varieties of rock, and the thicknesses and dis- 

 tribution of different deposits were also fully considered. The 

 following are the formations, in ascending order from the 

 Cretaceous rocks, as they were recognised in the first work by 

 Brongniart and Cuvier : 



9. Loess clay and pebble deposits, containing bones of large 

 terrestrial mammals. 



1. Unfossiliferous millstone quartz and fresh- 

 water limestone of Beauce (Orleans), con- 

 taining species of Planorbis, Cyclostoma, 

 Helix, and terrestrial plant-remains. 

 Sandstone, without molluscan remains (Fon- 

 Now rank tainebleau sandstone). 



as 6. Siliceous limestone, a facies of deposits 5 



Oligocene and 7 present in the southern parts of the 



deposits. basin. 



;. Sands and sandstone with molluscan re- 

 mains (Fontainebleau sandstone). 

 .. Gypsum and fresh- water marls, etc., with 

 Planorbis, Linnaeus, etc., passing upward 

 into marine oyster beds. 



Sands and coarse limestone series of Paris. 



2. Plastic clay without fossils. 



Now rank 



as 



Eocene 

 deposits. 

 i. Cretaceous rocks ; fifty fossil species were enumerated in 



the chalk deposits. 



A second and larger work was issued by the same authors 

 in 1811, with a special part devoted to geological descriptions, 



